Field called 'clean' causes cryptic error

[anonymous]

Naming a field 'clean' causes a rather cryptic message when adding a object through the admin interface. The error is "'NoneType' object is not callable".

Traceback:
File "/usr/local/lib/python2.6/dist-packages/django/core/handlers/base.py" in get_response
  111.                         response = callback(request, *callback_args, **callback_kwargs)
File "/usr/local/lib/python2.6/dist-packages/django/contrib/admin/options.py" in wrapper
  307.                 return self.admin_site.admin_view(view)(*args, **kwargs)
File "/usr/local/lib/python2.6/dist-packages/django/utils/decorators.py" in _wrapped_view
  93.                     response = view_func(request, *args, **kwargs)
File "/usr/local/lib/python2.6/dist-packages/django/views/decorators/cache.py" in _wrapped_view_func
  79.         response = view_func(request, *args, **kwargs)
File "/usr/local/lib/python2.6/dist-packages/django/contrib/admin/sites.py" in inner
  197.             return view(request, *args, **kwargs)
File "/usr/local/lib/python2.6/dist-packages/django/utils/decorators.py" in _wrapper
  28.             return bound_func(*args, **kwargs)
File "/usr/local/lib/python2.6/dist-packages/django/utils/decorators.py" in _wrapped_view
  93.                     response = view_func(request, *args, **kwargs)
File "/usr/local/lib/python2.6/dist-packages/django/utils/decorators.py" in bound_func
  24.                 return func(self, *args2, **kwargs2)
File "/usr/local/lib/python2.6/dist-packages/django/db/transaction.py" in inner
  217.                 res = func(*args, **kwargs)
File "/usr/local/lib/python2.6/dist-packages/django/contrib/admin/options.py" in add_view
  864.             if form.is_valid():
File "/usr/local/lib/python2.6/dist-packages/django/forms/forms.py" in is_valid
  121.         return self.is_bound and not bool(self.errors)
File "/usr/local/lib/python2.6/dist-packages/django/forms/forms.py" in _get_errors
  112.             self.full_clean()
File "/usr/local/lib/python2.6/dist-packages/django/forms/forms.py" in full_clean
  269.         self._post_clean()
File "/usr/local/lib/python2.6/dist-packages/django/forms/models.py" in _post_clean
  331.             self.instance.clean()

Exception Type: TypeError at /admin/library/song/add/
Exception Value: 'NoneType' object is not callable

[Aymeric Augustin]

In hindsight, it's obvious that calling a field clean, save or delete won't work as expected.

The docs could warn about such conflicts between field names and the model API: ​https://docs.djangoproject.com/en/dev/ref/models/instances/

[Tim Graham <timograham@…>]

In dd0cbc6bdccfc51329427b8a6023f6e866d48cba:

Fixed #16588 - Warned about field names that conflict with the model API

[Tim Graham <timograham@…>]

In a1d21c08774c87b8d2995aada5ad20c650ad7570:

[1.4.X] Fixed #16588 - Warned about field names that conflict with the model API

Backport of dd0cbc6bdc from master